If the the switch does not turn on/off the laserclub.
Short piece of link wire.
1. Remove both battery covers from the clubhead.
2. Remove batteries.
3.Carefully remove the the PCB along with the black metal mask by pushing the circuit board from the side without the switch.
4.Connect and solder a link between the three solder points shown in the diagram.
5. Insert the batteries and see if the problem has been fixed.
6. Re-assemble clubhead.